C Language Super Notes 2

Programming in “ C ” Index

   



   

   

Basic Concepts required for Introduction to C Introduction to C Operators in C Decision Control Structure  If Statement  If-Else Statement  If-Else-If Statement  Ternary Operator (ConditionalOperator)  ASCII  SwitchStatement Loop Control Structure  While loop  Do-While loop  For-loop Functions Storage Classes in C Pointers Arrays  Introduction to Arrays  PassingArrayelementstoFunction  Multidimensional Arrays  Two Dimensional Arrays  Three Dimensional Arrays String Functions Structures Union File Handling

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2 4 20 23 24 25 34 36 42 43 50 52 65 79 81 87 91 97 100 102 110 116 119

Basic Concepts Required for Introduction to C

User language (English language)

System language (Language of 0’s and 1’s i.e. Binary language)

Interpreter OS (Mediator, which converts user language Into system language) Introduction to Number system There are two types of number system in a computer i.e. Decimal number system and Binary number system.  Decimal Number System: The decimal number contains 10 natural numbers from 0 to 9, which are used by human being.  Binary Number System: The binary number system contains only two numbers i.e. 0 and 1 which is used by compiler, because compiler cannot understand any other language except 0 and 1 in the form of electronic signals. 0 1 0 1 0 1 0 1 0 1

ASCII ASCII ranges from 0 to 255. A – American S – Standard C – Code for I – Information I – Interchange In ASCII language, A – 65 B – 66 | | | Z – 90

a – 97 b – 98 | | | z – 122

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Conversion of Decimal number in to Binary number system 2 2 2 2 2 2

65 32 16 8 4 2 1

1 0 0 0 0 0

A

1

0

0

0

0

0

1

In System language, A= 1000001  Two directories called and are always included before starting the ‘C’ program. These are included in the given way. #include #include void main( ) { ------} printf – To print on screen. scanf - To get value from keyboard/user. stdio.h – standard input/output. header This directory is included because printf() and scanf() functions are present in this directory and if this directory is not included, printing and scanning is not possible. conio.h – console input/output. header This directory is included because clrscr() and getch() functions are present in this directory.  In C, semicolon (;) is used to terminate the statement.  In C, = Represents assignment operator E.g. a=10 (here 10 is assigned to variable a. = = Represents equality E.g. a==b(here variable a and variable b represents equality)

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Steps of C-program using flowchart Representation START

START

INPUT

a, b, c

CALCULATE

Datatype int

c=a+b

PRINT

Print c

STOP

STOP

10,20,4,9

int a, b;

%d

int a;

a

10 float

18.84,20.54

float a, b;

%f

float a;

a

18.84 char

‘a’, ‘i’, ‘b’

char a;

%c

char a;

a

c string

“chester”

char a[20];

%s

char a[7];

a

chester

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Introduction to ‘C’ Dennis Ritchie developed the ‘C’ language at AT & T Bell’s laboratory in 1972. It was originally written for programmes under the operating system UNIX. The early version written by Ken Thomson adopted in the form of a language by the initials BCPL which stands for Basic Combined Programming Language. To distinguish this language from BCPL, he termed it as ‘B’, the first character. When the language was modified and was improved to its present state, the second letter of BCPL, ‘C’ was chosen to represent new version. There is no single compiler for ‘C’. Many different organizations have written and implemented ‘C’ compiler. Power, Portability, Performance and flexibility are the most important results for ‘C’ popularity. ‘C’ combines the features of both high level language which is the functionality of the assembly language. Being a middle level language, it allows the manipulation of bits, bytes and the address directly make it more suitable for system programming and hence ‘C’ is mostly used for writing interpreters, compilers, assembler editions, database management. Advantages of ‘C’

   

It is a structural programming language. ‘C’ source code is portable. Being a middle level language suitable for commercial application. ‘C’ is designed so that compiler can translate a program into efficient machine instructions.

For Normal language

Alphabets

Words

Sentences

Paragraphs

‘C’ consist of

Alphabets Digits Special symbols

Constants Variables Keywords

Rules for C Program

 C is a case sensitive.

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Instructions

Programs

 All keywords have to be in lowercase.  Keywords have fixed meaning and are reserved i.e. keyword if, int, char.

Instructions about C program  ‘C’ always start from main() [because ‘C’ compiler starts compiling always from main() function.  There should be {(opening brace) and }(closing brace) to indicate the start and the end of C program.  For terminating the statements ;(semicolon) is used.  For inputting the data from the keyboard, scanf() function is used.  For output printf() function is used, where f is formatted input as well as for formatted output.  C has no specific rules for the position at which a statement is to be written. That’s why it is often called a free-form language.  Blank spaces may be inserted between two words to improve the readability of the statement. However, no blank spaces are allowed within a variable, constant or keyword. Basic Structure of C program DOCUMENTATION SECTION. LINK SECTION. DEFINITION SECTION. GLOBAL DECLARATION SECTION. main() : FUNCTION SECTION { Declaration part Executable part } Subprogram section function1 function2 (User defined functions) | | | | function n. Syntax of scanf() statement scanf(“control string”,&variable1 ,&variable2 - - -); address Syntax of printf() statement printf(“”,) where format string can be %f, %d, %c. Format String %f : It is used for declaring float variables. %d : It is used for declaring integer variables.

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%c : It is used for declaring character variables.

General Structure of C-program main() { declaration of variables/initialization scanf(“ _____ ”); printf(“ _____ ”); _______ _______ C-instructions _______

printf(“ _____ ”); } Comments

 Comments about the program should be enclosed within /* */  Any number of comments can be given at any place in the program.  Comments cannot be nested. For example, /*Cal of SI /* Author sam date 01/01/90 */*/ is invalid.  A comment can be split over more than one line, as in, /* This is a jazzy comment */ Comments should be used at any place where there is a possibility of confusion.  Any program is nothing but a combination of functions. main() is one such function. Empty parentheses after main are necessary.  The set of statements belonging to a function are enclosed within a pair of braces. For e.g. main() { statement 1; statement 2; statement 3; }  Any variable used in the program must be declared before using it. // Program to calculate simple interest. main() { int p,n; float r,si; p=1000;

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n=3; r=8.5; si=p*n*r/100; printf(“%f”,si); } In the above program we assumed the values of p, n and r to be 1000, 3 and 8.5. If we want to make a provision for supplying the values of p, n and r through the keyboard, scanf() function should be used. This is illustrated in the program shown below: main() { int p, n; float r, si; printf(“\nEnter values of p, n, r:”); scanf(“%d %d %f”,&p,&n,&r); si=p*n*r/100; printf(“%f”,si); } The 1st printf() statement outputs the message “Enter values of p, n, r” on the screen. Here we have not used any variables in printf(), which means that using variables in printf() is optional. Note that the ampersand (&) before the variables in the scanf() statement is a must. Also, note that the values for p, n and r to be supplied through the keyboard, must be separated by a blank, a tab or a newline. E.g. The three values separated by blank. 5 15.5 E.g. The three values separated by tab. 1000 5 15.5 E.g. The three values separated by newline. 1000 5 15.5 ‘C’-Character Set C-Character Set consists of alphabets, digits and special symbols. Alphabets: A---------Z a----------z Digits: 0--------9 Special symbols: +, -, =, {, }, [, ], ;, :, , ?, /, \, @, #, *

Constants Constant is a quantity which does not change during the execution of program. This quantity can be stored as a location in the memory of computer.

Variables Variable are those which can change during the execution of program (compilation of program). Example of constants and variables: 2a+3b=23

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Here a and b can vary but 2,3,23 cannot vary as those are values. Therefore, a &b are variables & 2,3,23 are constants.

//Program to convert Fahrenheit into celsius. #include #include void main() { float f,c; clrscr(); printf("\nEnter the value of fahrenheit:"); scanf("%f",&f); c=5.0/9*(f-32); printf("%f",c); getch(); } *************************************************************************** //Program to convert Pound into Kgs. #include #include void main() { float pound,kg; clrscr(); printf("\nEnter the pounds:"); scanf("%f",£); kg=pound/2.204; printf("Kg=%f",kg); getch(); } ******************************************************************************* //Program to calculate the area & volume of sphere #include #include void main() { int radius; float volume,area; clrscr(); printf("\nEnter the radius of sphere:"); scanf("%d",&radius); volume=(4.0/3)*3.14*radius*radius*radius;

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area=4*3.14*radius*radius; printf("Volume=%f Area=%f",volume,area); getch(); } ********************************************************************************

//Program to convert Km into m. #include #include void main() { float km,m; clrscr(); printf("\nEnter the value of Km:"); scanf("%f",&km); m=(1.0/1000)*km; printf("%f",m); getch(); } ******************************************************************************* //Program to convert Byte into Bits, Kilobytes, Megabytes #include #include void main() { float byte,bit,kb,mb; clrscr(); printf("\nEnter the bytes:"); scanf("%f",&byte); bit=1.0/8*byte; kb=byte*1000; mb=byte*1000000; printf("Bit=%f Kilobyte=%f Megabyte=%f",bit,kb,mb); getch(); } ******************************************************************************** //Program to calculate the sum of digits of three digit number //entered by user. #include #include void main() { int num,n1,n2,sum; clrscr(); printf("\nEnter any 3 digit number:");

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scanf("%d",&num); n1=num%10; num=num/10; n2=num%10; num=num/10; sum=n1+n2+num; printf("\nSum of 3 digits=%d",sum); getch(); }

************************************************************************************ //Program to calculate the sum of 1st and last digit of four digit //number entered by user. #include #include void main() { int num,n1,n2,sum; clrscr(); printf("\nEnter any 4 digit number:"); scanf("%d",&num); n1=num%10; n2=num/1000; sum=n1+n2; printf("\nSum of 1st and last digit=%d",sum); getch(); } ************************************************************************************ //Program to find the reverse of a 3 digit number //entered by user. #include #include void main() { int num,n1,n2,rev; clrscr(); printf("\nEnter any 3 digit number:"); scanf("%d",&num); n1=num%10; num=num/10; n2=num%10; num=num/10; rev=n1*100+n2*10+num; printf("\nReverse of 3 digit number=%d",rev); getch(); } ***************************************************************************

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Keywords Keywords are the words whose meaning has been already explained to the ‘C’ compiler. The keywords cannot be used as variables. There are 32 keywords in a ‘C’ language. The keywords are also called reserve words. E.g. if, int, else, float, goto. The 32 keywords are as follows: auto double

int

struct

break

else

long

switch

case

enum

register

typedef

char

extern

return

union

const

float

short

unsigned

continue

for

signed

void

default

goto

sizeof

volatile

Do

if

static

while

Data Type Data type specifies the size and arrangement of memory storage for an object of that type. Variable Declaration Every variable must have a datatype. Use a type specifier, such as char, int, short or long to show the variables type. Syntax: type name[value]; Data Type in ‘C’

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Character (char): 1 byte Integer (int): Positive 2 bytes Float (float): 4 bytes Data Type Modifiers



Signed/Unsigned type: Signed on integer in actual is redundant as the default integer assumes signed no. Signed is used to modify character (char), as character by default is unsigned. Unsigned can be applied to float.  Long/Short type: Long or short are applied to basic types. They are used when an integer of shorter or longer length than its normal length is required. Short is 16 bits, long is 32 bits. E.g. int a, char p, float length, double area, long distance, short miles.

C-Tokens In a passage of text, individual words and punctuation marks are called as tokens. Similarly in a C-program, the smallest individual units are known as C-Tokens. C has 6 types of tokens.

C-Tokens

Keywords E.g. float while if

Constants E.g. –15.5 100

Identifier

Strings

Operators

E.g. max amount(amt)

E.g. “ABC” “XYZ” “name”

E.g. +, -, *, /

Special Symbol

E.g. { } [] !s

Identifier Identifier refers to the names of variables, functions and arrays. These are user-defined names and consist of sequence of letters and digits with a letter as a first character. Both uppercase and lowercase letters are permitted and the underscore( _ ) is also permitted while defining the identifiers.

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Types of C Constants C-Constants can be divided into two major categories:  Primary Constants  Secondary Constants These constants are further categorized as follows:

C- Constants

Primary Constants

Secondary Constants

Numeric

Character

Constants

Constants

Integer

Real

Constants

Constants

Arrays Pointers Structures Union

Character

String Constant

er Constants

er Constants

 For constructing these different types of constants certain rules have been laid down and they are as follows: Rules for Constructing Integer Constants

 An integer constant must have at least one digit.

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    

It must not have a decimal point. It could be either positive or negative. If no sign precedes an integer constant it is assumed to be positive. No commas or blanks are allowed within an integer constant. The allowable range for integer constants is –32768 to +32767 for 16-bit numbers. It is defined in a program as ‘int’.  E.g. 426, +782, -8000, -7605 E.g. Invalid Valid 2_9 -15 -13m 2903 1.9 0

Rules For Constructing Real Constants Real Constants are often called Floating Point Constants. The real constants can be written in two forms, Fractional form and Exponential form. Rules for constructing real constants expressed in Fractional form:  A real constant must have at least one digit.  It must have a decimal point.  It could be either positive or negative.  Default sign is positive.  No commas or blanks are allowed within a real constant. E.g. +325.34, 426.0, -32.76, -48.5792 The exponential form of representation of real constant is usually used if the value of the constant is either too small or too large. In exponential form of representation, the real constant is represented in two parts. The part appearing before ‘e’ is called mantissa, whereas the part following ‘e’ is called exponent. Rules for constructing real constants expressed in exponential form:

   

The mantissa part and the exponential part should be separated by a letter ‘e’. The mantissa part may have a positive or negative sign. Default sign of mantissa part is positive. The exponent must have at least one digit which must be a positive or negative integer. Default sign is positive.  Range of real constants expressed in exponential form is –3.4e38 to 3.4e38. E.g. +3.2e-5, 4.1e8, -0.2e+3, -3.2e-5 Rules For Constructing Character Constants Rules for Constructing Single Character Constants A character constant is either a single alphabet, a single digit or a single special symbol enclosed within single inverted commas. Both the inverted commas should point to the left. For example, ’A’ is a valid character constant whereas ‘A’ is not.  The maximum length of a character constant can be 1 character. E.g. ’x’, ’z’, ’9’, ’=’ String Constants

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String: It is a sequence of characters. Rules For Constructing String Constants  It consists of multiple characters.  It is represented in double quotation marks. E.g. “Chester”, “x=ymg” Variable Names Variable names are names given to locations in the memory of computer where different constants are stored. These locations can contain integer, real or character constants.

Rules For Constructing Variable Names It must begin with a letter. Some system permits underscore ( _ ) as a first character. It is a combination of 1 to 8 characters. Some compilers allow the length of 40 characters. No commas or blanks are allowed for constructing the variables. It should not be a keyword. No special symbol other than underscore can be used. It is case sensitive. E.g.  Valid  Invalid

 x_y

 x-y



 xy

Datatypes It allows the programmer to select the type appropriate to the need of the application. It supports four classes.  Primary Datatype  User-Defined Datatype  Derived Datatype  Empty data set Primary Datatype There are 3 types of primary datatype.  Integer (int)  Real/Float (float)  Character (char)

 Integer (int) int (16-bit) short int (8-bit) long int (32-bit) unsigned short int (32-bit) unsigned long int (64-bit)

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 Character (char) Signed char Unsigned char

 Float/Real (float) Float Double Long double

Size and Ranges 1 byte=8 bits Datatype Range Char -128 to +127 Int -32768 to +32767 Float 3.4e-38 to 3.4e+38 Double 1.7e-308 to 1.7e+308

Size 1 byte 2 bytes 4 bytes 8 bytes

Declaration of Primary Data types Syntax: datatype a1, a2, a3 - - - - - - -an; E.g. int xyz; float val; char name[20]; float sal; User-Defined Datatype User-Defined type declaration Syntax: typedef type identifier; Where, type refers to existing datatype and identifier refers to the new name given to datatype. E.g. typedef int xyz; typedef int sal; C-Instructions

   

Type Declaration Instruction Input/Output Instruction Arithmetic Instruction Control Instruction

Type Declaration Instruction This instruction is used to declare the type of variables being used in the program. Any variable used in the program must be declared before using it in any statement. It is usually written at the beginning of the C-Program. E.g. int a; float amount;

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Input/Output Instruction This instruction is used to perform the function of supplying input data to a program and obtaining the output results from it. E.g. printf( ), scanf( ) Arithmetic Instruction This instruction is used to perform arithmetic operations between constants and variables. E.g. c=a+2b; In this instruction one arithmetic operator is used and also one assignment operator is used. This instruction is divided into 3 types. Integer Mode: In this mode arithmetic integer variables and arithmetic integer constants are used. E.g. int i; i=i+2; Real Mode: In this mode real variables and real constants are used. E.g. float b; float c; c=3.2+b; Mixed Mode: In this mode some operands are integer and some operands are real. E.g. float b; int c; float a; a=b+c+3 Note: C allows the variables or constants with arithmetic operators on the left side of equation. In C language 3+a=b is an invalid expression whereas b=3+a is a valid expression. Control Instructions This instruction is used to control the sequence of execution of various statements. E.g. while, for

Integer and float conversions The rules that are used for the implicit conversion of floating point and integer values in C are as follows:  An arithmetic operation between an integer and integer always yields an integer result.  Operation between a real and real always yields a real result.  Operation between an integer and real always yields a real result. E.g. Operation 5/2

Result 2

Operation 2/5

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Result 0

5.0/2 5/2.0 5.0/2.0

2.5 2.5 2.5

2.0/5 2/5.0 2.0/5.0

0.4 0.4 0.4

Type Conversion in Assignments

It may happen that the type of the expression and the type of the variable on the left side of the assignment operator may not be same. In such a case the value of the expression is promoted or demoted depending on the type of the variables on the left side of =. E.g. int i; float b; i=3.5; b=30; Here in the first assignment statement though the expression’s value is a float(3.5) it cannot be stored in ‘i’ since it is an integer. In such a case the float is demoted to an integer and then its value is stored. Hence what gets stored in ‘i’ is 3. Exactly opposite happens in the next statement. Here, 30 is promoted to 30.000000 and then stored in ‘b’, since ‘b’ being a float variable cannot hold anything except a float value. Thus while storing the value the expression always takes the type of the variable into which its value is being stored. Consider the complex expression in the given program fragment: float a, b, c; int s; s=a*b*c/100+32/4-3*1.1; Here, in the assignment statement some operands are integers whereas others are floats. As we know during evaluation of the expression the integers would be promoted to floats and the result of the expression would be a float. But when this float value is assigned to ‘s’ it is again demoted to an integer and then stored in ‘s’. E.g. ‘k’ is an integer variable and ‘a’ is a real variable. Arithmetic Instruction k=2/9 k=2.0/9 k=2/9.0 k=2.0/9.0 k=9/2 k=9.0/2

Result

Arithmetic Instruction a=2/9 a=2.0/9 a=2/9.0 a=2.0/9.0 a=9/2 a=9.0/2

0 0 0 0 4 4

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Result 0.0 0.2222 0.2222 0.2222 4.0 4.5

k=9/2.0 k=9.0/2.0

4 4

a=9/2.0 a=9.0/2.0

4.5 4.5

Hierarchy of Operations

1st priority

*, /, %

2nd priority

+, -

3rd priority

=

The priority or precedence in which the operations in an arithmetic statement are performed is called as Hierarchy of operations. The usage of operators in general is as follows:

 In case of a tie between operations of same priority preference is given to the operator, which occurs first. For example, consider the statement, z = a*b+c/d; Here, a*b will be performed before c/d even though * and / has same or equal priority. This is because * appears prior to the / operator.  Also, if there are more than one set of parentheses, the operations within the innermost parentheses will be performed first, followed by the operations within the second innermost pair and so on.  Always, a pair of parentheses should be used. Imbalance of the right and left parentheses is a common error. Q.1 Determine the hierarchy of operations and evaluate the following expression: i=2*3/4+4/4+8–2+5/8 Stepwise evaluation of this expression is shown below: i=2*3/4+4/4+8–2+5/8 i=6/4+4/4+8–2+5/8 Operation : * i=1+4/4+8–2+5/8 Operation : / i=1+1+8–2+5/8 Operation : / i=1+1+8–2+0 Operation : / i=2+8–2+0 Operation : + i = 10 – 2 + 0 Operation : + i=8+0 Operation : i=8 Operation : + Q.2 Determine the hierarchy of operations and evaluate the following expression: k=3/2*4+3/8+3 Stepwise evaluation of this expression is shown below: k=3/2*4+3/8+3 k=1*4+3/8+3 Operation : / k=4+3/8+3 Operation : * k=4+0+3 Operation : / k=4+3 Operation : + k=7 Operation : + 1) ab – cd = a * b – c * d

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2) 3) 4)

5)

(m + d) (x + y) = (m * d) * (x + y) 2x2 + 5x + 15 = 2 * xe2 + 5 * x + 15 x + y + z = ( x + y + z) / (b + c) b+c

3xy y m+2 3(m+2) = (3* x*y)/(m+2) – (y/3* (m+2))

Q.1 WAP to calculate the area of triangle. Q.2 WAP to calculate the area of square. Q.3 WAP to calculate the area and circumference of a circle. Q.4 WAP to calculate the area of a triangle when three sides of a triangle are given. Q.5 WAP to interchange two integer variables.  With using 3rd variable.  Without using 3rd variable. Q.6 WAP to convert Fahrenheit into Celsius. Q.7 WAP to convert Pound into kilograms. Q.8 WAP to calculate area and volume of a sphere. Q.9 WAP to convert Kilometers into meters. Q.10 WAP to convert Byte into bits, kilobytes, megabytes. Q.11 WAP to calculate the sum of digits of three-digit number entered by user. Q.12 WAP to calculate the sum of 1st and last digit of four-digit number. Q.13 WAP to find the reverse of three-digit number.

stdio.h

getchar() putchar() (For single character i/o)

gets() puts() (multiple character i/o including space)

printf() scanf() (multiple character i/o but in formatted manner without space)

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**************************************************** ************************ //WAP to print a single character using getchar() and putchar() #include #include void main() { char a; clrscr(); a=getchar(); putchar(a); getch(); } ********************************************************************** //WAP to print a string without space using printf() and scanf() #include #include void main() { char username[20]; clrscr(); printf("\nEnter your name:"); scanf("%s",&username); printf("\nUsername=%s",username); getch(); } ********************************************************************************* //WAP to print a string including space using gets() and puts #include #include void main() { char username[20]; clrscr(); printf("\nEnter your name:"); gets(username); printf("Username=");

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puts(username); getch(); } *****************************************************************************

//WAP to print the name of the student using gets() and puts(), print //the marks of maths, science nad english and also print the total and //average of the student. #include #include void main() { int maths, sci, eng; float total, avg; char sname[20]; clrscr(); printf("\nEnter the name of a student:"); gets(sname); printf("\nEnter the marks of maths, science and english:"); scanf("%d %d %d",&maths,&sci,&eng); total=maths+sci+eng; avg=total/3; clrscr(); printf("********************Student Details***********************"); printf("\nThe name of the student is:"); puts(sname); printf("The marks of Maths is:%d",maths); printf("\nThe marks of Science is:%d",sci); printf("\nThe marks of English is:%d",eng); printf("\nThe total marks of the student is:%f",total); printf("\nThe average of the student is:%f",avg); printf("\n**********************************************************"); getch(); } *********************************************************************** //WAP which prints the employee no, employee name and salary and using it //calculate its da, hra and total salary. #include #include void main() {

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int eno; float salary,da,hra,ts; char ename[20]; clrscr(); printf("\nEnter the name of the employee:"); gets(ename); printf("\nEnter the Employee id:"); scanf("%d",&eno); printf("\nEnter the salary of the employee:"); scanf("%f",&salary); da=0.35*salary; hra=0.11*salary; ts=da+hra+salary; clrscr(); printf("******************Employee Details***********************"); printf("\nThe name of the employee is:"); puts(ename); printf("The employee id is:%d",eno); printf("\nThe salary of the employee is:%f",salary); printf("\nDA:%f",da); printf("\nHRA:%f",hra); printf("\nTotal Salary of the employee is:%f",ts); printf("\n*********************************************************"); getch(); } ***********************************************************************

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Operators in C There are 8 types of operators in C and they are:  Arithmetic Operators  Relational Operators  Logical Operators  Conditional Operators  Assignment Operators  Increment and Decrement Operators  Bitwise Operators  Special type Operators. Arithmetic Operators Arithmetic Operators are +, -, *, /, %. OP1

OP2

RESULT

int

Int

int

25

int

float

float

float

int

float

float

float

float

Relational Operators Relational Operators are > (greater than) < (less than) >= (greater than equal to) - Bitwise Right Shift b

B is greater

A is greater

STOP 29

#include #include void main() { int maths,sci,eng; float total,avg; char sname[20]; clrscr(); printf("\nEnter the name of the student:"); gets(sname); printf("\nEnter the marks of maths, science and english:"); scanf("%d %d %d",&maths,&sci,&eng); total=maths+sci+eng; avg=total/3; printf("\nStudent name is:"); puts(sname); if(avg=35 && avg=45 && avg=60 && avg=75 && avgn3) { printf("\nLargest number is n1"); } else printf("\nn3 is largest"); } else { if(n2>n3) printf("\nn2 is largest"); else printf("\nn3 is largest"); } getch();} *********************************************************************** //WAP which reads a marks of 5 subjects entered by student and check whether //the student has passed or fail. If passed calculate the percentage marks //of student and also print the division of the student. #include #include void main()

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{ int m1,m2,m3,m4,m5,per; clrscr(); printf("\nEnter the marks of 5 subjects:"); scanf("%d %d %d %d %d",&m1,&m2,&m3,&m4,&m5); if(m1>=40 && m2>=40 && m3>=40 && m4>=40 && m5>=40) { printf("\nStudent is passed"); per=(m1+m2+m3+m4+m5)/5; if(per>=75) printf("\nCongrats, U have got distinction"); if(per>=60 && per=50 && per=40 && perb) && (b!=0)) { x=a/b; printf("\n%f",x); } else if((b>a) && (a!=0)) { x=b/a; printf("\n%f",x); } getch(); } *********************************************************************** //WAP to find whether the entered year is a leap year or not. #include #include void main() { int year; clrscr(); printf("\nEnter the year:"); scanf("%d",&year); if((year%4==0 && year%100!=0) || (year%400==0)) { printf("\nThe year is a leap year"); } else printf("\nThe year is not a leap year"); getch(); } *********************************************************************** //WAP for function of calculator which performs addition, subtraction, //multiplication and division. #include

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#include void main() { int x; float a,b,c; clrscr(); printf("\nMENU\n1.ADDITION\n2.SUBTRACTION\n3.MULTIPLICATION\n4.DIVISION \nEnter Choice"); scanf("%d",&x); printf("\nEnter 2 numbers:"); scanf("%f %f",&a,&b); if(x==1) { c=b+a; printf("\nThe result of addition is %f",c); } else { if(x==2) { c=a-b; printf("\nThe result of subtraction is %f",c); } else { if(x==3) { c=a*b; printf("\nThe result of multiplication is %f",c); } else { if(x==4) { c=a/b; printf("\nThe result of division is %f",c); } else { printf("\nInvalid Choice"); } } } } getch(); } *********************************************************************** #include #include void main() { int age; clrscr(); printf("\nEnter your age:");

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scanf("%d",&age); if(age=1 && age=18 && age=45 && ageb?a:b); printf("\n%d is big",big); getch(); } *********************************************************************** #include #include void main() { int a,b,c,big; clrscr(); printf("\nEnter any three numbers:"); scanf("%d %d %d",&a,&b,&c); big=(a>b?(a>c?a:c):(b>c?b:c)); printf("\n%d is biggest",big); getch(); } *********************************************************************** ASCII (American Standard Code for Information Interchange) 0 48 | | | | | | 9 57

42

65 | | | 90

A | | | Z

97 | | | 122

a | | | z

#include #include void main() { char ch; clrscr(); printf("\nEnter any character:"); scanf("%c",&ch); printf("\n%c",ch); getch(); } *********************************************************************** #include #include void main() { char ch; clrscr(); printf("\nEnter any character:"); scanf("%c",&ch); printf("\n%d",ch); getch(); } ********************************************************************** #include #include void main() { char ch; clrscr(); printf("\nEnter any character:"); scanf("%c",&ch); if(ch>=48 && ch=65 && ch=97 && ch